How to Freeze Rhubarb: The Easy Method for Future Use

Fresh rhubarb is one of the highlights of late spring and early summer, but did you know that it freezes beautifully for future use? Read on for the easiest way to freeze fresh rhubarb so you can enjoy its tart flavor year-round. Plus, I’ll share some favorite rhubarb recipes to try with your frozen stash!

Freshly harvested red rhubarb stalks in a large metal bowl on grassy ground.

Rhubarb is a tart vegetable that’s often used in favorite desserts like rhubarb crisp, rhubarb sauce, and rhubarb compote. Fresh rhubarb only in season for a short period in late spring and early summer, so if you love this delicious vegetable, it’s a good idea to stock up while it’s available. Fortunately, freezing rhubarb is a great way to preserve it for future use, whether you grow your own rhubarb or buy it from a local store or farmer’s market.

In this post, we’ll go through the step-by-step process of freezing fresh rhubarb to ensure the best quality and shelf life, including tips and tricks for preparation, storage, and usage.

What is Rhubarb?
When is Rhubarb in Season?
Why Freeze Rhubarb?
Step-by-Step Guide to Freezing Rhubarb
Storage
Different Methods for Freezing Rhubarb
Tips for Freezing Rhubarb
How to Use Frozen Rhubarb
FAQs
Rhubarb Recipes to Try

Frozen rhubarb pieces on parchment paper

What is Rhubarb?

Before we get into the freezing process, let’s talk a little bit about rhubarb. Rhubarb is a perennial plant that is commonly grown for its edible stalks. It’s botanically classified as a vegetable, but it’s often used in sweet dishes like pies, crisps, and sauces. Rhubarb has a tart, tangy flavor that pairs well with sweet ingredients like sugar, honey, and fruit. It’s also rich in nutrients like fiber, vitamin K, and potassium.

When is Rhubarb in Season?

Rhubarb is a short-season vegetable that is typically in season from late spring to early summer. The exact timing can vary depending on your location and climate. If you’re lucky enough to have your own rhubarb plant, you’ll know it’s ready to harvest when the stalks are at least 12 inches long and about the thickness of your thumb. When buying rhubarb at the grocery store or farmer’s markets, look for bright, firm stalks with no blemishes or brown spots.

Why Freeze Rhubarb?

While rhubarb season is short, freezing your rhubarb harvest allows you to enjoy it all year long. Freezing rhubarb is also a great way to prevent waste if you have excess rhubarb that you can’t use right away. Plus, frozen rhubarb is just as nutritious and flavorful as fresh rhubarb, so you can use it in all your favorite recipes without sacrificing quality.

Step-by-Step Guide to Freezing Rhubarb

Step 1: Wash and trim the rhubarb

Fresh rhubarb stalks being washed under the faucet in a white kitchen farm sink.

Start by washing the rhubarb stalks thoroughly under cold water. Discard any green rhubarb leaves, which contain oxalic acid and should not be eaten

Step 2: Dry the rhubarb

Drying rinsed rhubarb stalks in a blue kitchen towel.

Once the rhubarb is cleaned, dry the stalks thoroughly with a kitchen towel or paper towels. This step helps to remove excess water and prevent freezer burn.

Step 3: Cut the rhubarb into smaller pieces

Cutting fresh rhubarb stalks into small pieces with a knife on a cutting board.

Trim off the tough strings at the base of the stalk. Cut the rhubarb stalks into 1-inch pieces or smaller, depending on your preference.

Step 4: Arrange the rhubarb in a single layer on a rimmed baking sheet

Spreading cut rhubarb pieces out into one even layer on a parchment lined baking sheet.

Arrange the rhubarb pieces in a single layer on a rimmed baking sheet lined with parchment paper. Be sure to leave enough space between the pieces so that they are not touching each other.

Step 6: Freeze the rhubarb

Transferring the flash frozen rhubarb pieces from the parchment paper into the freezer bag.

Place the baking sheet in the freezer and freeze the rhubarb for 1-2 hours, or until it is mostly frozen. Once the rhubarb is partially frozen, you can transfer it to freezer containers or plastic bags for future use.

Remove excess air by pressing down on the bag or by using a straw to suck the air out of the bag. You can also vacuum seal the bags with a vacuum sealer to remove excess air. Be sure to label the containers with the date and amount of rhubarb.

Labeling a freezer bag with contents: rhubarb, date: 6/26/22, with a black sharpie pen.

Storage

Store frozen rhubarb in freezer safe bags or airtight containers in the freezer at a temperature of 0˚F (-18˚C) or lower for up to 12 months.

Use the rhubarb pieces right from the freezer in recipes or thaw it in its bag or container placed inside a bowl overnight in the fridge.

Frozen rhubarb pieces in a labeled ziploc freezer bag

Different Methods for Freezing Rhubarb

Tray method: This method involves flash freezing the individual pieces rhubarb on a tray in a single layer before transferring it to a freezer-safe bag or container. This method is the best way to keep the rhubarb pieces from freezing in one clump. The free flowing pieces are easy to add to baking or cooking recipes.

Dry pack method: This method involves packing the raw rhubarb pieces into a plastic container or ziploc freezer bag without flash freezing them first. It’s an easy way to freeze smaller amounts of rhubarb, but they may clump together. This method is fine to use for sauces or jam, where the rhubarb will be cooked down.

Blanching method: This method involves blanching rhubarb pieces in boiling water for 1-2 minutes, depending on the size of the pieces and transferring them to an ice bath to stop the cooking process. Some say this step helps to preserve the color and texture of the rhubarb, but I have not seen a significant difference in quality, taste or texture between frozen raw rhubarb or frozen blanched rhubarb. Rhubarb is an acidic vegetable so it doesn’t benefit from blanching the same way low-acid vegetables like peas, carrots and corn do. If you decide to blanch the rhubarb, be sure to dry the blanched pieces well to remove as much excess liquid as possible to prevent ice crystals from forming.

Tips for Freezing Rhubarb

To freeze large quantities of rhubarb, it’s best to use plastic containers or freezer-safe bags.
Be sure to remove as much air as possible from the container or bag to prevent freezer burn.
Label the container or bag with the date and the amount of rhubarb inside.
Rhubarb freezes best when it’s fresh, so try to freeze and store it as soon as possible.

Fun Fact: Did you know that rhubarb is technically a vegetable? Despite its tart flavor and common use in sweet desserts, it is actually classified as a vegetable due to its botanic characteristics.

How to Use Frozen Rhubarb

Now that you’ve successfully frozen your rhubarb, you might be wondering what to do with it next. One great way to use frozen rhubarb is to make a rhubarb sauce or stewed rhubarb. Simply thaw the rhubarb pieces in the refrigerator or at room temperature and then place them in a pot with a small amount of water and sugar to taste. Cook until the rhubarb is soft and then optionally blend it until it’s smooth.

Another delicious way to use frozen rhubarb is to make a rhubarb crisp or rhubarb crumble. This classic dessert is easy to make and always a crowd-pleaser. Simply toss the frozen rhubarb pieces with sugar and your favorite crisp topping (such as oats, flour, butter, and brown sugar) and bake until golden brown and bubbling.

Frozen rhubarb bakes up perfectly as a galette filling with juicy strawberries. Tuck the sweet and tart filling into a flaky pie crust for a no-fuss elegant dessert.

Strawberry rhubarb crumble topped with vanilla ice cream and daisy flowers served out in white bowls with green trim with the tart pan of crumble in next to them.

FAQs

How long does frozen rhubarb last?

Properly frozen, packaged and stored rhubarb will last for up to 12 months.

Can I freeze rhubarb without blanching it first?

Yes, rhubarb freezes well without blanching it first. Rhubarb is an acidic vegetable and its acidity helps to deter the naturally occurring enzymes found in vegetables that cause them to break down over time.

Can I use frozen rhubarb in recipes that call for fresh rhubarb?

Yes, frozen rhubarb works just as well as fresh rhubarb in many recipes including baked goods, sauces, and jams.

What is the best way to thaw frozen rhubarb?

Thaw frozen rhubarb in its bag or container overnight in the fridge. Place it in a bowl to collect any condensation.

Can I freeze rhubarb sauce or compote?

Yes, rhubarb sauce freezes well. Store it in a freezer safe airtight container for up to 6 months. Thaw rhubarb compote or freezer jam in the fridge overnight before using and then use it up within 1 week.

What are some other ways to preserve rhubarb for future use?

You can preserve rhubarb by canning it as a jam, sauce or in a syrup pack. Follow safe food canning guidelines for shelf stable rhubarb that will keep for up to 12-18 months.

How much rhubarb should I freeze at once?

As little or as much as your freezer can hold. If you’re following the tray method, then freeze it in small batches of how many trays you can fit into your freezer at a time.

Cut raw rhubarb pieces on a parchment paper lined sheet pan.

Freezing rhubarb is a great idea to preserve this delicious vegetable for future use, especially during the short season of late spring and early summer. By following these simple steps and using the best methods for freezing rhubarb, you can enjoy this tart and versatile ingredient all year long. Try some of my family’s favorite rhubarb recipes listed below or experiment with your own and discover why rhubarb is one of our favorite vegetables.

Rhubarb Recipes to Try